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Diffstat (limited to 'src/shell-wobbly-effect.c')
| -rw-r--r-- | src/shell-wobbly-effect.c | 216 |
1 files changed, 216 insertions, 0 deletions
diff --git a/src/shell-wobbly-effect.c b/src/shell-wobbly-effect.c new file mode 100644 index 000000000..eb1d87484 --- /dev/null +++ b/src/shell-wobbly-effect.c @@ -0,0 +1,216 @@ +/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */ + +/* + * Copyright (C) 2014 Endless Mobile + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of the + * License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA + * 02111-1307, USA. + * + * Written by: + * Jasper St. Pierre <jstpierre@mecheye.net> + */ + +#include "config.h" + +#include "shell-wobbly-effect.h" + +struct _ShellWobblyEffectPrivate +{ + int bend_x; + + int tex_width, tex_height; + CoglPipeline *pipeline; + + int tex_width_uniform; + int bend_x_uniform; +}; +typedef struct _ShellWobblyEffectPrivate ShellWobblyEffectPrivate; + +G_DEFINE_TYPE_WITH_PRIVATE (ShellWobblyEffect, shell_wobbly_effect, CLUTTER_TYPE_OFFSCREEN_EFFECT); + +static const gchar *wobbly_decls = + "uniform int tex_width;\n" + "uniform int bend_x;\n"; +static const gchar *wobbly_pre = + "float bend_x_coord = (float(bend_x) / tex_width);\n" + "float interp = (1 - cos(cogl_tex_coord.y * 3.1415926)) / 2;\n" + "cogl_tex_coord.x -= (interp * bend_x_coord);\n"; + +/* XXX - clutter_effect_get_paint_volume is fucking terrible + * and I want to kill myself */ +static gboolean +shell_wobbly_effect_get_paint_volume (ClutterEffect *effect, + ClutterPaintVolume *volume) +{ + ShellWobblyEffect *self = SHELL_WOBBLY_EFFECT (effect); + ShellWobblyEffectPrivate *priv = shell_wobbly_effect_get_instance_private (self); + + float cur_width; + cur_width = clutter_paint_volume_get_width (volume); + cur_width += ABS (priv->bend_x); + clutter_paint_volume_set_width (volume, cur_width); + + /* Also modify the origin if it bends to the left. */ + if (priv->bend_x < 0) + { + ClutterVertex origin; + clutter_paint_volume_get_origin (volume, &origin); + origin.x += priv->bend_x; + clutter_paint_volume_set_origin (volume, &origin); + } + + return TRUE; +} + +static gboolean +shell_wobbly_effect_pre_paint (ClutterEffect *effect) +{ + ShellWobblyEffect *self = SHELL_WOBBLY_EFFECT (effect); + ShellWobblyEffectPrivate *priv = shell_wobbly_effect_get_instance_private (self); + + if (!clutter_actor_meta_get_enabled (CLUTTER_ACTOR_META (effect))) + return FALSE; + + /* If we're not doing any bending, we're not needed. */ + if (priv->bend_x == 0) + return FALSE; + + if (!clutter_feature_available (CLUTTER_FEATURE_SHADERS_GLSL)) + { + /* if we don't have support for GLSL shaders then we + * forcibly disable the ActorMeta + */ + g_warning ("Unable to use the ShellWobblyEffect: the " + "graphics hardware or the current GL driver does not " + "implement support for the GLSL shading language. The " + "effect will be disabled."); + clutter_actor_meta_set_enabled (CLUTTER_ACTOR_META (effect), FALSE); + return FALSE; + } + + if (!CLUTTER_EFFECT_CLASS (shell_wobbly_effect_parent_class)->pre_paint (effect)) + return FALSE; + + ClutterOffscreenEffect *offscreen_effect = CLUTTER_OFFSCREEN_EFFECT (effect); + CoglObject *texture; + + texture = clutter_offscreen_effect_get_texture (offscreen_effect); + cogl_pipeline_set_layer_texture (priv->pipeline, 0, texture); + + priv->tex_width = cogl_texture_get_width (texture); + priv->tex_height = cogl_texture_get_height (texture); + + cogl_pipeline_set_uniform_1i (priv->pipeline, priv->tex_width_uniform, priv->tex_width); + + return TRUE; +} + +static void +shell_wobbly_effect_paint_target (ClutterOffscreenEffect *effect) +{ + ShellWobblyEffect *self = SHELL_WOBBLY_EFFECT (effect); + ShellWobblyEffectPrivate *priv = shell_wobbly_effect_get_instance_private (self); + CoglFramebuffer *fb = cogl_get_draw_framebuffer (); + ClutterActor *actor; + guint8 paint_opacity; + + actor = clutter_actor_meta_get_actor (CLUTTER_ACTOR_META (effect)); + paint_opacity = clutter_actor_get_paint_opacity (actor); + + cogl_pipeline_set_color4ub (priv->pipeline, + paint_opacity, + paint_opacity, + paint_opacity, + paint_opacity); + + cogl_framebuffer_draw_rectangle (fb, priv->pipeline, + 0, 0, priv->tex_width, priv->tex_height); +} + +static void +shell_wobbly_effect_dispose (GObject *object) +{ + ShellWobblyEffect *self = SHELL_WOBBLY_EFFECT (object); + ShellWobblyEffectPrivate *priv = shell_wobbly_effect_get_instance_private (self); + + g_clear_pointer (&priv->pipeline, cogl_object_unref); + + G_OBJECT_CLASS (shell_wobbly_effect_parent_class)->dispose (object); +} + +static void +shell_wobbly_effect_class_init (ShellWobblyEffectClass *klass) +{ + GObjectClass *object_class = G_OBJECT_CLASS (klass); + ClutterEffectClass *effect_class = CLUTTER_EFFECT_CLASS (klass); + ClutterOffscreenEffectClass *offscreen_class = CLUTTER_OFFSCREEN_EFFECT_CLASS (klass); + + offscreen_class->paint_target = shell_wobbly_effect_paint_target; + effect_class->pre_paint = shell_wobbly_effect_pre_paint; + effect_class->get_paint_volume = shell_wobbly_effect_get_paint_volume; + object_class->dispose = shell_wobbly_effect_dispose; +} + +static void +update_uniforms (ShellWobblyEffect *self) +{ + ShellWobblyEffectPrivate *priv = shell_wobbly_effect_get_instance_private (self); + cogl_pipeline_set_uniform_1i (priv->pipeline, priv->bend_x_uniform, priv->bend_x); +} + +static void +shell_wobbly_effect_init (ShellWobblyEffect *self) +{ + static CoglPipeline *pipeline_template; + + ShellWobblyEffectPrivate *priv = shell_wobbly_effect_get_instance_private (self); + + if (G_UNLIKELY (pipeline_template == NULL)) + { + CoglSnippet *snippet; + CoglContext *ctx = clutter_backend_get_cogl_context (clutter_get_default_backend ()); + + pipeline_template = cogl_pipeline_new (ctx); + + snippet = cogl_snippet_new (COGL_SNIPPET_HOOK_TEXTURE_LOOKUP, wobbly_decls, NULL); + cogl_snippet_set_pre (snippet, wobbly_pre); + cogl_pipeline_add_layer_snippet (pipeline_template, 0, snippet); + cogl_object_unref (snippet); + + cogl_pipeline_set_layer_null_texture (pipeline_template, + 0, /* layer number */ + COGL_TEXTURE_TYPE_2D); + } + + priv->pipeline = cogl_pipeline_copy (pipeline_template); + priv->tex_width_uniform = cogl_pipeline_get_uniform_location (priv->pipeline, "tex_width"); + priv->bend_x_uniform = cogl_pipeline_get_uniform_location (priv->pipeline, "bend_x"); + + update_uniforms (self); +} + +void +shell_wobbly_effect_set_bend_x (ShellWobblyEffect *self, + int bend_x) +{ + ShellWobblyEffectPrivate *priv = shell_wobbly_effect_get_instance_private (self); + + if (priv->bend_x == bend_x) + return; + + priv->bend_x = bend_x; + update_uniforms (self); + clutter_effect_queue_repaint (CLUTTER_EFFECT (self)); +} |